MiniMax H3 API Key

The MiniMax H3 API Key node is the least exciting node in this pack and the one you can't skip. It does nothing by itself - no generation, no upload, no poll - it just holds two strings and hands them to every generation node in the MiniMaxH3/Direct category. Its output is a custom MINIMAX_H3_KEY type that only the pack's own nodes accept, so you can't accidentally wire your key into something that has no business reading it. Think of it as the credential vault for your workflow: drop one on the canvas, fill it in, and it fans out to Text-to-Video, First-Last-Frame, and Reference nodes.

How it works

Every generation node in the pack takes a key input. Under the hood the Key node bundles your base_url and token into a single object, strips any trailing slash off the base URL, and passes it along. When a generation node fires, it builds an Authorization: Bearer <token> header and talks to <base_url> - uploading files, creating a task, and polling until your video is done.

Two things the source checks before it lets you proceed: if token is empty you get MiniMax H3 token is required. and if base_url is empty you get the matching error. That's it. The node is deliberately dumb.

The two inputs that matter

• base_url - the endpoint of your MiniMax H3-compatible service, no trailing slash. The default is https://metaso.cn/api/minimax.
• token - the bearer token for the Authorization header.

Worth a beat on that default, because it's the author's own pitch. The README strongly recommends metaso.cn, a third-party reseller claiming "80% off" MiniMax's official price (768P at 0.09 CNY/s, 2K at 0.15 CNY/s). I searched the community corpus for any signal on that domain and came up with zero threads - no praise, no complaints, nothing. That doesn't mean it's a scam, but it does mean the "80% off" figure is vendor marketing you haven't seen verified anywhere. The safe play: either try it with a small credit purchase first, or skip it entirely and set base_url to the official MiniMax platform API at https://api.minimaxi.com. Any server that implements the H3 API spec works here.

One more habit worth keeping: the token lives in plain text inside your workflow JSON. That's the normal shape of an API-wrapper node (see the KB's security notes on the LLMVISION incident), but it means you should treat this file like a credential, not like a checkpoint name. Don't share workflow files with your token pasted in, and don't hardcode a key into a workflow you're going to publish.

Install

Same story as every node in this pack. ComfyUI Manager → Install via Git URL, paste https://github.com/meta-sota/ComfyUI-MiniMaxH3-API.git, restart. Or manually:

cd ComfyUI/custom_nodes
git clone https://github.com/meta-sota/ComfyUI-MiniMaxH3-API.git
cd ComfyUI-MiniMaxH3-API
pip install -r requirements.txt

The only pip dependency is aiohttp, but note this pack is written against ComfyUI's newer native node API (comfy_api.latest, IO.ComfyNode), so it needs a reasonably recent ComfyUI - the author tests against 0.30.0. On an old build it simply won't register. There are no model downloads and no GPU requirement; all the compute happens on MiniMax's side.

Common issues

• "MiniMax H3 token is required." - you left the token blank. Fill it in.
• 401s at generation time - token and base_url don't match. A mk- token from metaso.cn won't authenticate against api.minimaxi.com and vice versa; they're separate accounts.
• Nothing in the node list after install - almost always an outdated ComfyUI. Update before you debug anything else.